Etymologically
Log in

opaque

This is the current revision of this entry, as edited by bogdan on 31 October 2026 at 22:59. This address is a permanent link to this version.
Changes in this edit History

Pronunciation

  • UK: /əʊˈpeɪk/[1]
  • US: /oʊˈpeɪk/[1]

Etymology

It was first inherited from Middle English opake,[2][3][4] borrowed from Latin opācus (“shaded, shady, dark”).[5][3][6][2] The OED treats that first record as an isolated early borrowing, and the later use as partly borrowed from Middle French opaque (about 1500) and partly a fresh borrowing of the Latin;[5][7][8] the present spelling, rare before the 19th century, follows the French.[5][3][9] The American Heritage Dictionary likewise takes the English word from both the Middle English opake and French opaque.[10] The Latin adjective, which in post-classical Latin also meant obscure or mysterious, is of unknown origin.[5][6][3][11] De Vaan rejects the old comparison with Sanskrit and Old Church Slavonic words for "turned away, behind", which would not give the Latin form, and mentions as a mere possibility a compound with the root of vacuus (“empty”) and vānus (“empty”);[12] Merriam-Webster suggests a connection with ob (“towards, before”).[13] Related forms are opaco, opaco and opaco.[5]

Earliest recorded meaning

Lying in shade; dark, not lit: about 1440, in a Middle English translation of Palladius on farming, where fruit is to be hung up in place opake, in a dark place, glossed derke.[5][2][6]

Semantic evolution

The literal Latin sense "shaded, dark" is now rare,[5][7] and the modern meaning, "not letting light through, not transparent", is recorded from 1631,[5] or from the 1640s in Etymonline.[6] From 1646 it was also used of a surface that does not reflect or give out light, dull.[5] Milton's Paradise Lost has body opaque, one of Johnson's quotations in 1755.[14] The figurative sense "hard to understand, obscure" dates from 1761, in Sterne's Tristram Shandy,[5][6] and for a time (about 1789–1886) the word also meant dull-witted, a sense still listed by Collins.[5][15] In 1818 a London guide used opaque as slang for "drunk", contrasting it with a more transparent companion.[16] Science extended it in 1860 to bodies that block other radiation, such as heat, sound or X-rays,[5][15] and linguistics from 1949 to words whose meaning can no longer be read from their parts.[5] The noun dates from 1742 (a place of darkness) and the verb, to make opaque, from 1718.[5][13]

Timeline

  • c. 1440 – opake, dark, shaded.[5][2][3]
  • 1631 – not letting light through, not transparent.[5]
  • 1646 – not reflecting light, dull.[5]
  • 1718 – verb, to make opaque.[5][13]
  • 1742 – noun, a region of darkness (obsolete by 1877).[5][13]
  • 1761 – hard to understand, obscure.[5][6]
  • 1860 – impervious to other radiation, such as heat or X-rays.[5]
  • 1949 – in linguistics, of a word whose meaning cannot be deduced from its parts.[5]

Meanings

Adjective

  1. Not letting light pass through; neither transparent nor translucent: opaque glass in the bathroom window.[15][13][5]
  2. Not letting other radiation, such as heat, sound or X-rays, pass through.[15][5]
  3. Hard to understand; obscure: The report was written in opaque legal language.[15][5][10]
  4. Not reflecting light; dull, without lustre.[15][13][5]
  5. (archaic) Dark, not lit; lying in shadow.[13][5][7]

Noun

  1. An opaque pigment or paint, used to block out parts of a photographic negative or print.[13][15]

Verb

  1. To make opaque, or to block out parts of a negative with opaque paint.[13][5]

Word family

  • opaquely
  • opaqueness
  • opacify
  • semiopaque
  • subopaque
  • radiopaque
  • opacity

References

  1. ^ a b Wiktionary, the free dictionary, https://en.wiktionary.org
  2. ^ a b c d Kurath, Hans; Kuhn, Sherman M.; Lewis, Robert E., eds. (1952–2001), Middle English Dictionary, Ann Arbor: University of Michigan Press; online edition ed. Frances McSparran et al. (2000–2018)
  3. ^ a b c d e Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
  4. ^ Weekley, Ernest (1921), An Etymological Dictionary of Modern English, London: John Murray
  5. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z 27 28 Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
  6. ^ a b c d e f Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
  7. ^ a b c Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
  8. ^ Hoad, T. F., ed. (1986), The Concise Oxford Dictionary of English Etymology, Oxford: Clarendon Press
  9. ^ Stevenson, Angus, ed. (2010), Oxford Dictionary of English, 3rd ed., Oxford: Oxford University Press
  10. ^ a b The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt
  11. ^ Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
  12. ^ de Vaan, Michiel (2008), Etymological Dictionary of Latin and the other Italic Languages, Leiden Indo-European Etymological Dictionary Series 7, Leiden; Boston: Brill
  13. ^ a b c d e f g h i Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
  14. ^ Johnson, Samuel (1755), A Dictionary of the English Language, London; 4th ed. 1773; Johnson's Dictionary Online, ed. Beth Rapp Young et al.
  15. ^ a b c d e f g Collins English Dictionary (2023), Glasgow: HarperCollins
  16. ^ Green, Jonathon (2010), Green's Dictionary of Slang, London: Chambers; digital ed. 2016–, https://greensdictofslang.com